#include<bits/stdc++.h>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/rope>
using namespace std;
using namespace __gnu_pbds;
using namespace __gnu_cxx;


#define mod 1000000007
 /*
    /\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/ *** Debugging Start *** \/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/
*/
void __print(int x) {cerr << x;}
void __print(long x) {cerr << x;}
void __print(long long x) {cerr << x;}
void __print(unsigned x) {cerr << x;}
void __print(unsigned long x) {cerr << x;}
void __print(unsigned long long x) {cerr << x;}
void __print(float x) {cerr << x;}
void __print(double x) {cerr << x;}
void __print(long double x) {cerr << x;}
void __print(char x) {cerr << '\'' << x << '\'';}
void __print(const char *x) {cerr << '\"' << x << '\"';}
void __print(const string &x) {cerr << '\"' << x << '\"';}
void __print(bool x) {cerr << (x ? "true" : "false");}
template<typename T, typename V>
void __print(const pair<T, V> &x) {cerr << '{'; __print(x.first); cerr << ','; __print(x.second); cerr << '}';}
template<typename T>
void __print(const T &x) {int f = 0; cerr << '{'; for (auto &i: x) cerr << (f++ ? "," : ""), __print(i); cerr << "}";}
void _print() {cerr << "]\n";}
template <typename T, typename... V>
void _print(T t, V... v) {__print(t); if (sizeof...(v)) cerr << ", "; _print(v...);}
#ifndef ONLINE_JUDGE
#define debug(x...) cerr << "[" << #x << "] = ["; _print(x)
#else
#define debug(x...)
#endif
/*
    /\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/ *** Debugging Ends *** \/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/
*/
using namespace __gnu_pbds;
template <typename T>
using ordered_set = tree<T, null_type, less_equal<T>, rb_tree_tag, tree_order_statistics_node_update>;

/// Some frequent usable functions
#define int                        long long
void add(int &a,int b){a+=b;if(a>mod)a-=mod;}
void sub(int &a,int b){a-=b;if(a<0)a+=mod;}
void mul(int &a, int b) {a=1ll * a * b % mod;}
template<typename T> T pow(T a,T b, long long m){T ans=1; while(b>0){ if(b%2==1) ans=(ans*a)%m; b/=2; a=(a*a)%m; } return ans%m; }
int powmod(int a,int b)
{int res = 1;while(b){if(b&1){res = (res * a)%mod;}b= b/2;a = (a*a)%mod;}return res;}
int _ceil(int, int);
int _floor(int a, int b) { return b < 0 ? _floor(-a, -b) : a < 0 ? -_ceil(-a, b) : a / b; }
int _ceil(int a, int b) { return b < 0 ? _ceil(-a, -b) : a < 0 ? -_floor(-a, b) : (a + b - 1) / b; }

// int gcd(int a, int b, int &x, int &y) {if (a == 0) {x = 0; y = 1;return b;
//     }int x1, y1;int d = gcd(b%a, a, x1, y1); x = y1 - (b / a) * x1;y = x1;return d;}
// int find(int v){return v==parent[v]?v:parent[v] = find(parent[v]);}
// void merge(int i,int j)
//     {i = find(i);j = find(j);if(i == j)return;parent[parent[i]] = parent[j];cmp--;}

/*
    /\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/ *** Directions in grids *** \/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/
*/
// int dy[4] = {0,0,1,-1}, dx[4] = {1,-1,0,0}; // 4 Direction
// int dx[] = {1,-1,0,0,1,1,-1,-1} , dy[] = {0,0,1,-1,1,-1,1,-1};  // 8 Direction
// int dx[] = {1,-1,1,-1,2,2,-2,-2} , dy[] = {2,2,-2,-2,1,-1,1,-1};  // Knight moves
// int dx[] = {2,-2,1,1,-1,-1} , dy[] = {0,0,1,-1,1,-1};  // Hexagonal Direction
#pragma GCC target ("avx2")
#pragma GCC optimization ("O3")
#pragma GCC optimization ("unroll-loops")
#define fast ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL)
#define sp(a , x) cout << fixed << setprecision(a) << x << endl;
#define endl "\n"
#define pb push_back
#define pf push_front
#define ub upper_bound
#define lb lower_bound
#define F first
#define S second
#define mset(a, b) memset(a, b, sizeof a)
#define sz(x) ((int)(x.size()))
#define sqr(x) ((x) * (x))
#define graph vector<int>
#define vi vector<int>
#define vvi vector<vector<int>>
#define pi pair<int,int>
#define all(c)                      c.begin() , c.end()
#define rep(i,a) for(int i=0;i<a;i++)
#define rrep(i,a,b) for(int i=a;i>=b;i--)
#define iter(it,a) for(auto it=a.begin();it!=a.end();it++)
#define PQP priority_queue<pi, vector<pi>, greater<pi>>
#define PQI priority_queue<int, vector<int>, greater<int>>
#define dbg debug
#define inf (int)1e16
const long double EPS = 0.0000000001;
const long double PI = 3.1415926535897932384;
//vec.resize(unique(all(vec)) - vec.begin());
 int dy[4] = {0,0,1,-1}, dx[4] = {1,-1,0,0};

  /// define some data.......
const int N = (int)1e4+15;
int dp[N][N];
int a[N];

int f(int l, int r)
{
   if( l == r ) return a[l];
   if(l+1 == r) return max(a[l], a[r]);

   int &ret = dp[l][r];
   if( ret != -1) return ret;

     int op1 = a[l] + min(f(l+1, r-1), f(l+2, r));
     int op2 = a[r] + min(f(l+1, r-1), f(l, r-2));

     ret = max(op1, op2);

     return ret;

}

void solve()
{
  mset(dp, -1);
  int n;
  cin >> n;

  for(int i=1;i<=n;i++)
  {
     cin >> a[i];
  }

  cout<<f(1, n)<<"\n";


}
int32_t main()
  {
     fast;
     int test =1;
    // cin >> test;
     int tc=1;
     while(test--)
     {
        solve();


     }

  }